A New Approach to the Integration of Computational Fluid Dynamics Tools to Promote Learning and Innovation in Aerospace Engineering

A new approach to computational fluid dynamics code validation is developed that gives proper consideration to experimental and simulation uncertainties. The comparison error is defined as the difference between the data and simulation values and represents the combination of all errors. The validation uncertainly is defined as the combination of the uncertainties in the experimental data and the portion of the uncertainties in the CFD prediction that can be estimated. This validation uncertainty sets the level at which validation can be achieved. The criterion for validation is that the magnitude of the comparison error must be less than the validation uncertainty. If validation is not accomplished, the magnitude and sign of the comparison error can be used to improve the mathematical modeling. Consideration is given to validation procedures for a single code, multiple codes and/or models, and predictions of trends. Example results of verification/validation are presented for a single computational fluid dynamics code and for a comparison of multiple turbulence models. The results demonstrate the usefulness of the proposed validation strategy. This new approach for validation should be useful in guiding future developments in computational fluid dynamics through validation studies and in the transition of computational fluid dynamics codes to design.

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New Approach of Gas–Liquid Computational Fluid Dynamics Simulations for the Study of Minimum Quantity Cooling With Airblast Plain-Jet Injectors

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4024632 ◽

2013 ◽

Vol 135 (4) ◽

Cited By ~ 2

Author(s):

Christophe Diakodimitris ◽

Youssef R. Iskandar ◽

Patrick Hendrick ◽

Pierre Slangen

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Single Phase ◽

Continuous Phase ◽

Navier Stokes ◽

Two Phase ◽

New Approach ◽

Metal Machining ◽

Dynamics Simulations ◽

Liquid Flows

Due to the complexity of multiphase flows, they are often studied with numerical simulations. These simulations must be validated with experimental results. This paper introduces a new approach to initialize the continuous phase of gas–liquid flows generated by airblast nozzles for microlubrication applications with a recently modified commercial computational fluid dynamics (CFD) code FINE™/Open. Microlubrication is a technology used in metal machining where the coolant flow rate is lower than with conventional flood cooling. In this paper, single-phase gas and two-phase liquid–gas flows are studied. The continuous phase is simulated using Reynolds-averaged Navier–Stokes (RANS) equations coupled with a k–ε turbulence model and the dispersed phase is simulated using a Lagrangian method. To validate these simulations, particle image velocimetry (PIV) and particle dynamics analysis (PDA) measurements have been performed. This study illustrates the possibility of performing complex two-phase simulations with the help of single-phase studies to initialize the continuous phase of the flow (i.e., the gas). The single-phase flow also helps in estimating the magnitudes of the droplet velocities.

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